Malaysia symposium examines Asian developments 08 Nov 2018

Roland Herr for TunnelTalk

Held in Kuala Lumpur on 18 and 19 September the joint Chinese-Malaysian tunnel symposium had a total of 18 keynote lectures and was organised by the China Civil Engineering Society (CCES) and the Institution of Engineers, Malaysia (IEM). As Roland Herr reports it was a successful practice run for the WTC 2020 and demonstrated the rise of Asia's influence.

“It is the first time ever that a symposium between the two ITA member nations, China and Malaysia has been organised,” announced Dr Teik Aun Ooi, Organising Chairman of the SEASET 2018 (South East Asia symposium and exhibitions on the challenges and strategic solutions of high profile projects on tunnels 2018) to more than 300 participants from across the globe in Kuala Lumpur, Malaysia.

Held on 18 and 19 September the joint symposium had a total of 18 keynote lectures and was organised by the China Civil Engineering Society (CCES) and the Institution of Engineers, Malaysia (IEM).

The presentations gave an overview of upcoming projects in China and Malaysia, notably:

Railway and highway tunnels in China under operation, construction or in the planning stages. Presentation by Prof Hong Kairong, chief engineer of China Railway Tunnel Group.

More than 14,500 railway tunnels with an overall length of approximately 15,300km are under operation including 130 long railway tunnels with a total length of 1,800km and nine extra long tunnels of more than 20km. Under construction are 156 extra long tunnels (about 2,100km) and six tunnels longer than 20km. Apporximately 270 extra long tunnels of more than 830km are in the planning phase, and 19 tunnels of more than 20km long.

With a combined length of 15,300km more than 16,200 highway tunnels are under construction, containing more than 900 extra long tunnels totalling approximately 4,000km and 3,840 long tunnels with a length of 6,600km. Approximately 190km highway tunnels with a length between 11 and 15km are under construction and planned to be ready for operation by 2022. About 175km extra long highway tunnels with a length between 10 and 22km are in the planning stage.

Construction technologies for the Gaoligongshan Tunnel of the Dali-Ruili railway

Prof Hong Kairong also presented the Gaoligongshan Tunnel project of the 330km long railway between Dali and Ruili in the western part of the Yunnan Province. With a total length of 34.5km and an overburden of 1,155m the Gaoligongshan Tunnel is currently the first ultra-long single-track railway tunnel under construction in China, using a hard rock TBM and NATM for the excavation. The deepest vertical shafts are 762m deep with internal diameters of 6m. The ground conditions have been exceptionally challenging and water inflows of a maximum of 6,270m3 per day.

Technical challenges of super-long mountainous tunnels at great depth

Prof Jenny Yan Jinxiu, Vice President of the ITA (International Tunnelling and Underground Space Association) and the Chinese Tunnelling and Underground Works Society of CCES spoke of the challenges facing super-long tunnels, namely the validity and accuracy of geological investigation at great depth, the long construction period, and the difficulties in disaster prevention and evacuation in specific geological conditions (high ground stress, high geothermal temperature and high pressure groundwater).

Clients perspective of MRT Line 2 in Kuala Lumpur

No one could have foreseen the dramatic cessation and then re-enstatement of the contract with MMC Gamuda for MRT Line 2 but Poh Seng Tiok, planning and design director for Mass Rapid Transit Corporation (MRTC), gave an overview of the state of the construction works on MRT Line 2 at the time of the conference.

He stated: “Looking ahead, the KVMRT project has not only opened up tremendous underground works and new frontiers for underground space engineering in Malaysia, but it is tempting to potentially revise and re-purpose geological knowledge-base of underground Kuala Lumpur armed with the wealth of subsurface information as well as the unique geotechnical accomplishments and experience to be gained from this remarkable underground construction.”

Variable density slurry tunnel boring machine

Gusztav GUS Klados, Director Tunnels for the Underground Works Package of Contractor MMC Gamuda KVMRT (T) Sdn. Bhd. for the Sungai Buloh – Serdang – Putrajaya (SSP) Line (MRT Line 2), Kuala Lumpur, described the development and the success of the variable density slurry (VD) TBMs used on the KVMRT Line 1. He explained the complex geology of the Sungai Buloh – Kajang SBK Line (MRT Line 1) tunnels mostly located under and around the most expensive real estate in downtown Kuala Lumpur, where significant subsidence induced by tunnelling were just not acceptable.

The stringent demands of circumstances forced the development of a new tunnel boring technology, capable of handling mixed face conditions in karst while remaining usable in the Kenny Hill Formation. The new machine configuration allowed five different operational modes, only one of them requiring a simple physical conversion to EPB configuration since some of the planned drives in the SBK Line had to pass the transition area from Kuala Lumpur Limestone to the Kenny Hill Formation, where the EPB method is the obvious choice. Herrenknecht and MMC Gamuda JV developed the new technology naming it the Variable Density Slurry or Mixshield TBM. The machines allowed the contractor to complete the tunnels of MRT Line 1 (SBK Line) within budget and on schedule.

Status of underground works for SSP Line (MRT Line 2) as end of July 2018Source: Poh Seng Tiok

Challenges and advances in tunnelling in Malaysia

Tunnelling in Malaysia can be attributed to the successful implementation of the SMART project started in 2003 to solve the problem of frequent flooding of the Kuala Lumpur Business District. The Malaysian capital city also faces traffic congestion which is made worse each time there is a heavy downpour. The water during heavy rainstorm is diverted from the city centre using the SMART tunnel as a by-pass. The challenges facing tunnel construction are in the treacherous Kuala Lumpur limestone formation where sinkhole formation poses a great threat. The other factor spurring on the growth of tunnels in Malaysia is the shortage of water supply in Kuala Lumpur and the Klang Valley areas which is undergoing rapid urbanisation. The construction of an interstate water transfer tunnel from Karak in Pahang and Ulu Langat in Selangor through the main mountain range of Titiwangsa in the granite formation also faces great challenges due to the rock burst and groundwater issues. This project started soon after the completion of the SMART tunnel.

The commencement of the SBK MRT Line 1 in 2011 marked the start of major tunnelling activities in Kuala Lumpur city centre, following the SSP MRT Line 2 which is now back under construction following the new agreement between the Government and contractor over cost reductions.

Preview to the World Tunnel Congress 2020 in Kuala Lumpur

The SEASET conference was well organised and ran impeccably to time due to the professionalism and efficiency of the presenters however this made the job of the translators going from Chinese to English and vice versa very hard. Sometimes, during video presentations you could hear the interpreter fighting for air trying to keep up with the video.

But this Chinese-Malaysian symposium was a great general rehearsal and preview for the WTC 2020. The recently held conference, the CTUC (China Tunnel and Underground works Conference) and ITA awards in Chuzhou last week was a great chance for the Malaysian organisers to spark the interest of the huge number of Chinese.

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